Hot inert gas purging for filter blowback process
AssigneeWestinghouse Electric Corp.
InventorsRodney L. Griffin, David F. Ciliberti, Thomas E. Lippert
Life of this patent
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Abstract
A filter cleaning process for filters for separating particulates from a hot gas stream using hollow, tubular filter elements. Blowback and hot purge gas systems provide for cleaning of the filter elements and maintenance of the blowback system clear of the solids or condensation products that might form during separation. The process is especially useful in filtering solids from a hot, corrosive gaseous stream, such as a zirconium tetrachloride process gaseous stream, where the gas stream contains gaseous constituents that are subject to condensation directly to a solid during separation of the particulates and prior to discharge from the filtering apparatus.
Claims15
In a process for filtering particulate materials from a hot gas stream of the type which contain gaseous constituents that have a condensation temperature and are subject to condensation or solids formation during separation of the particulate material through cooling of the gas stream, and in which ceramic filter and blowback gas ports and blowback conduits are utilized for cleaning said filter, and in which a purge gas flow which continually exits through the blowback gas ports is utilized;
- the improved method which comprises:
- preheating said purge gas flow to above the condensation temperature of said component of the gas stream which component is subject to condensation or solids formation during the separation of the particulate material through cooling of the gas stream, whereby condensation in the blowback gas ports and blowback conduits is substantially avoided.
In a process for filtering particulate materials from a gas stream having a temperature of at least 450.degree. C. said gas stream being of the type which contain at least one gaseous constituent that is subject to condensation or solids formation during separation of the particulate material through cooling of the gas stream and in which a ceramic filter and blowback gas ports are utilized, and utilizing a pulse of blowback gas for cleaning said filter and a purge gas flow which continually exits through the blowback gas ports;
- the improved method which comprises:
- preheating said purge gas to above 450.degree. C.
Dependencies are inferred from the claim text.